Coronavirus updates: US reports nearly 300,000 new cases in all-time high

After authorizing the Houston Health Department to open the city's first free COVID-19 vaccination clinic on Jan. 2, the call center to make vaccination appointments is already overwhelmed, said Houston Mayor Sylvester Turner on Twitter Saturday.

Turner said at a press conference later in the day that the call center received 250,000 calls by 7:30 a.m. when they only planned to provide 750 vaccinations. They turned to on-site registration to handle all the demand.

Turner plans to open "mega-sites" to provide vaccines in the near future, he said. Staff planned to stay late on Saturday and vaccinate about 1,000 people, the mayor said.

Houston reported 2,334 more cases and eight new deaths on Saturday.

ABC News' Matthew Fuhrman and Abby Shalawylo contributed to this report.

New York has become the fourth state to cross 1 million COVID-19 cases, the governor announced Saturday.

New York joined California, Texas and Florida in hitting that mark. Illinois, at over 975,000 cases, is likely to join those four in the coming days. California has already crossed 2 million cases.

"With 2020 now behind us, we can see brighter days ahead, but to get there quickly, it's going to take all New Yorkers staying smart and staying united," Gov. Andre Cuomo said in a statement. "We have the vaccine, and that is good news, but it will be months before we've reached critical mass, making it as important as ever that we do not let COVID fatigue get the best of us."

The state reported just over 15,000 new cases on Saturday and a percent-positivity rate that has grown to 7.45%. That number was around 1% for much of the summer after being the epicenter for the pandemic in the spring.

There was some good news on Saturday as Cuomo reported there were 72 fewer people hospitalized due to the virus in the state.

Officials continue to fear growing cases in the new year after Christmas and New Year's travel in recent weeks. New York crossed 30,000 deaths earlier this week.

UNC Health of Chapel Hill, North Carolina, confirmed it acquired 725 COVID vaccines origanally intended for the Orange County health department on Thursday night, WTVD reported.

In an emailed statement, the Orange County health department said, "UNC Health was notified that Orange County had a number of vaccine vials available for immediate use.

"UNC Health worked closely with Orange County to ensure that all of the vaccines would be used with zero waste and that all of these shots would go to either Phase 1-A personnel or staff who work with COVID-19 patients in some capacity.

"This cooperation was a success, and all of the available stock was used appropriately."

-ABC News' Joshua Hoyos

Florida Gov. Ron DeSantis won’t allow local governments to enforce their mask mandates, causing frustration among some mayors, reported WPLG.

“We can give out citations and we can urge people and we can give out masks, and we’ve given out thousands, but we don’t have the ability to mandate it in any way that’s effective,” Miami Beach Mayor Dan Gelber told WPLG.

“He continues to say that we don’t want the federal government to tell us what to do, states are better because it should be local controlled,” said Broward County Mayor Steve Geller. “But when we here in Broward are asking for local control, we’re not getting it."

-ABC News' Ahmad Hemingway